Sucker rod pumps, also known as beam pumps, are a widely used artificial lift method in the oil and gas industry. They are particularly well-suited for low-to-medium production rate wells and have been a reliable and cost-effective solution for decades. These pumps are designed to efficiently lift well fluids from substantial depths, making them a versatile choice for a wide range of well conditions.
Structure
As mentioned earlier, sucker rod pumps are classified into top-anchored (RHA, RWA) and bottom-anchored (RHB, RWB) types, based on the positioning of the stationary assembly. The pump's structure consists of two primary assemblies: the plunger-inserted pump barrel assembly and the outer stationary assembly.
The plunger-inserted pump barrel assembly is the core component responsible for fluid displacement. It comprises a pump barrel, typically made of steel or corrosion-resistant alloys, and a reciprocating plunger that travels within the barrel. The plunger is connected to the sucker rod string, which extends from the surface to the downhole pump.
The stationary assembly houses the intake and discharge valves, which control the flow of well fluids into and out of the pump barrel. This assembly also includes sealing elements and anchoring mechanisms to secure the pump in place within the well.
Working Principle
The operating principle of beam pumps is based on the reciprocating motion of the plunger, driven by the surface pump jack. During the upstroke, the stationary valve (intake valve) and the annular valve open, while the traveling valve (discharge valve) closes. This action allows well fluids to fill the pump barrel as the plunger rises, lifting the fluids above it to the surface.
On the downstroke, the traveling valve opens, while the stationary and annular valves close, creating a two-stage compression within the pump barrel. This compression forces the well fluids through the traveling valve, above the plunger, preparing for the next upstroke cycle.
The sucker rod string transmits the reciprocating motion from the surface pump jack to the downhole pump, enabling the cyclical lifting of well fluids to the surface.
Advantages and Servicing
One of the key advantages of sucker rod pumps is their ease of servicing and maintenance. Unlike tubing pumps, which require the removal of the entire tubing string to access the pump, beam pumps can be pulled for servicing by retrieving the sucker rod string alone. This significantly reduces downtime and associated costs, especially in deeper wells.
Common issues that may require servicing include worn or parted sucker rods, plunger sticking due to coal fines ingress (requiring jarring action), slippage or failure of pump barrel sealing elements causing leaks, and stationary valve leaks. Regular monitoring and preventive maintenance can help mitigate these issues and extend the operational life of the pump.
Application Scope
Sucker rod pumps are primarily suited for low-to-medium fluid production rates in vertical or moderately deviated wells (deviation <75°). They are particularly advantageous in wells with minor sand, coal fines, and scaling issues, as their robust design can withstand these challenging conditions.
While sucker rod pumps excel in certain applications, their performance may be limited in high-rate wells or wells with severe deviation or complex trajectories. In such cases, alternative artificial lift methods, such as electric submersible pumps or gas lift systems, may be more appropriate.
Operators can make informed decisions by understanding the structure, working principles, advantages, and application scope of beam pumps to optimize production and minimize operational costs in their oil and gas assets.
Vigor will provide you with a reliable solution, Please contact us at info@vigorpetroleum.com.
